A verb appearing as 1st sg. ᴹQ. rerin “I sow” with past tense rende in The Etymologies of the 1930s, derived from the root ᴹ√RED “scatter, sow” (Ety/RED). Here the ancient d became r as it usually did after vowels.

Neo-Quenya: In both Outline of Phonetic Development (OP1) from the 1930s and Outline of Phonology (OP2) from the 1950s, Tolkien indicated that when medial d followed an r, it could dissimilate to l rather that following its usual development to r (PE19/32, PE19/70). In OP2 he gave the verb Q. ral- < √RAD as an example (PE19/99). Thus it is possible that ᴹQ. rer- should be revised to ᴺQ. rel- “to sow” to fit this rule, as suggested by Elaran. However, since Tolkien had this rule in the 1930s but still had ᴹQ. rer- in The Etymologies, I prefer to think the dissimilation of medial d to l was a sporadic change, and would therefore retain rer- for purposes of Neo-Quenya.

Conceptual Development: The Qenya Lexicon of the 1910s had ᴱQ. orya- “sow” in the Qenya Lexicon under the early root ᴱ√ORO² (QL/70).